An idea was different types of bones as well. A legbone would make an excellent club, while a rib would make a very good spear
Materials, though. Bone, obsidian, flint, leather, hardened leather, granite, jade, the materials for weeping blade like quartz. Petrified bone is a great idea as well. No metals though, except maybe copper.
As for making them vary...
Flint should be the most damaging material for cutting and stabbing, but it's brittle and can break.
Copper should be the best material for blunt weapons, as it's harder to break and does decent damage.
Bone should be the best all around. Fairly durable and doing good damage with any weapon type.
Petrified bone can be the best material, high damage and hard to break, but is also very hard to shape, meaning you'll be using these as you find them, as blunt weapons, no other types.
Obsidian breaks very easily, but is light, accurate and has half-decent damage.